firmware editing on arduino ide

I put a different type of thermistor in my hotend and when I try to edit the firmware in the Arduino ide none of the tabs like configuration.h and pinn.h open when I launch the marlintaz.ino from the firmware download on the lulzbot website. I think it has to do with not installing the proper library files to Arduino ide folders. I’m not very experienced in using the Arduino, I have download zip. libraries from GitHub successfully but following the same process I have no luck. I feel like I tried everything. My hotend is reading about 50c hotter than it is because I cant change the thermistor type in the firmware

If you haven’t already, check out http://reprap.org/wiki/Rambo_firmware, especially the section about adding the RAMBo plugin to Arduino.